levo

Photosynthesis Uses Light Energy to Synthesise Organic Molecules

The Light-independent Stage: Rubisco, Glycerate-3-phosphate and Triose Phosphate

  • 3 things to know
  • A2 Unit 3

Overview

Recall questions on Rubisco, Glycerate-3-phosphate and Triose Phosphate.

What you need to know

Answer each one before you reveal it.

Your recallNot started
Key term

Name the carbon dioxide acceptor and the enzyme that fixes carbon dioxide, and say what is formed first.

Key term

What is the first carbohydrate of photosynthesis, how is hexose made from it, and what proportion regenerates ribulose bisphosphate?

Key term

Name the five-carbon acceptor molecule that takes up carbon dioxide.

Questions from this subtopic

Each one with the model answer underneath.

  1. 1

    Where in the chloroplast does the light-independent stage occur?

    Model answer

    It occurs in the stroma.

  2. 2

    Why does the light-independent stage stop soon after a plant is placed in darkness, even though it does not use light directly?

    Model answer

    It depends on a continuing supply of ATP and reduced NADP from the light-dependent stage, and these are quickly used up once light is no longer available.

  3. 3

    Name the five-carbon acceptor molecule that takes up carbon dioxide.

    Model answer

    The acceptor is ribulose bisphosphate, usually shortened to RuBP.

  4. 4

    Name the enzyme that catalyses the fixation of carbon dioxide.

    Model answer

    The enzyme is ribulose bisphosphate carboxylase, known as Rubisco.

  5. 5

    What happens immediately after carbon dioxide combines with ribulose bisphosphate?

    Model answer

    An unstable six-carbon compound is formed, which splits at once into two molecules of the three-carbon compound glycerate-3-phosphate.

  6. 6

    Why does one molecule of carbon dioxide give rise to two molecules of glycerate-3-phosphate?

    Model answer

    The single carbon of the carbon dioxide is added to the five carbons of ribulose bisphosphate, and the resulting six-carbon compound divides into two equal three-carbon molecules.

Other ways to work this

The same content, four other ways.

What is inside Levo

Six ways to work the same material.

1Closed book
2Open book
3Closed book

The 3-step method, run for you

Answer cold, learn it, then prove it stuck. Levo tracks the jump between your first attempt and your last.

Chemical Elements Are Joined Together to Form Biological Compounds
Cell Structure and Organisation
Cell Membranes and Transport
Biological Reactions Are Regulated by Enzymes

Cram a whole paper in one sitting

Sort every topic into what you know and what you do not, then drill only the weak ones.

A zygote.
diploidhaploidtriploid

Blank Blitz makes facts automatic

Rapid timed gap-fills on the terms and numbers you need to recall without thinking.

AThe numbers span several orders of magnitude.
BA logarithmic scale fits them all on one axis.
CThe exponential phase then appears as a straight line.

Build It gets the exam shape right

Assemble a full-mark answer from its marking points, in the order an examiner wants them.

Mitosis is division of the nucleus.
TrueFalse

Test It catches misconceptions

Spot the fault in a statement. The traps are the mistakes students actually make.

721941163128510

Brain Breaks between sessions

Short focus games to reset attention, so the next set lands better than the last.

Every question in Photosynthesis Uses Light Energy to Synthesise Organic Molecules, on a schedule.

Attempt a question from memory, write the correct version, then attempt it again. Levo records the jump between your first attempt and your last, and brings each question back on the day you are due to forget it.

Or £46 a year, about £3.83 a month. Cancel anytime.